Anna Vakili will criticise Curtis Pritchard for advising her boyfriend to pursue his passion for another woman on Love Island.
Jordan Hames confided in Curtis, who advised him to follow his instincts and talk to India Reynolds.
This led to drama in the villa as Anna confronted her partner over his plans to pursue the newcomer.
Curtis had gossiped to his partner Maura Higgins, who then warned her friend Anna – and both women were left questioning the integrity of the dancer.
The simmering tensions in the villa come before the announcement of a double dumping.
Anna tells an apologetic Curtis in scenes to air on Wednesday night: “I don’t know if you’re a good person.
“A good person would never tell someone to do that to their other half. Do you not care about me one tiny bit? I’ve been living with you for two months.”
Disappointment in Curtis is not confined to Anna, and his own partner Maura expresses doubt over his character.
She will say: “For Curtis to give that advice to Jordan, it baffles me. If he was my boyfriend, is that what he would do?
“Would he pull a girl before chatting to his girlfriend?”
She will add to Curtis: “She’s my friend. I care about her. I’m angry that he asked her to be his girlfriend a few days ago and now he’s cracking on with someone else.”
While islanders navigate the aftermath of an expletive-laden confrontation between Anna and Jordan, the Love Island babies have arrived for the couples to care for.
As they begin managing the new responsibility, a dumping is announced, with two couples set to leave the show.
As the end of the current series draws near, ITV has announced there will be a double dose of Love Island next year.
The broadcaster said a new villa will be used in South Africa in early 2020, before filming returns to Majorca in the summer.